Nos gustaría dar las gracias a la Fundación de Cirugía Torácica para la Investigación y la Educación por su apoyo financiero a este proyecto.

1. Preparación preoperatoria y anestesia <ol><li> Asegúrese de seguir una técnica estéril durante todo el procedimiento. Coloque todos los instrumentos. </li><li> Girar en la cama control de la temperatura antes de la inducción de la anestesia de modo que pueda calentar a la temperatura apropiada (36,5 ° C). Potencia en el monitor de perfusión Doppler láser de modo que puede arrancar durante la inducción. </li><li> Coloque el ratón en la cámara de inducción. <ol><li> Controle cuidadosamente la frecuencia respiratoria del ratón durante la inducción. </li><li> Tan pronto como la frecuencia respiratoria se ha ralentizado visualmente, quitar el ratón de la cámara de inducción. </li><li> Realice pizca dedo del pie para evaluar la adecuación de la anestesia. </li></ol></li><li> Con el ratón adecuadamente anestesiado, el lugar del ratón en la posición supina. </li><li> Inserte cara en cono de la nariz y asegure todas las extremidades a la mesa de la calefacción. <ol><li> Preste especial atención a que las extremidades están asegurados en posición anatómica, sin deviatia un lado. Si el ratón está colocado de forma incorrecta, es difícil evitar la transección de la arteria torácica interna durante la esternotomía. </li></ol></li><li> El uso de máquinas de cortar o crema de depilación disponibles en el mercado, eliminar el vello del tórax en la línea media y la parte inferior izquierda la superficie ventral de la extremidad. <ol><li> Si se usa crema de depilación, evite dejar la crema en su lugar por más de 30 segundos, se pueden producir quemaduras como alcalinos. </li></ol></li><li> Valorar concentración vaporizador anestésico volátil para mantener la anestesia adecuada. <ol><li> Fracciones vaporizador esperados son entre 1-5% utilizando isoflurano con alto flujo de O2. </li><li> Concentración vaporizador anestésico volátil debe ajustarse para mantener la anestesia durante la estimulación quirúrgica, manteniendo la respiración espontánea. </li></ol></li></ol> 2. Colocación Laser Doppler sonda rectal <ol><li> Inserte la sonda rectal lubricado en el recto del ratón. Asegure en su lugar para operAting cama. </li><li> Ajuste la cama de calefacción para una temperatura rectal objetivo de 36,5 ° C. </li><li> Hacer de la pequeña incisión sobre la arteria femoral del ratón y diseccionar la piel lejos del tejido subcutáneo. </li><li> Inserte la sonda Doppler láser sobre la arteria femoral. </li><li> Ajuste las posiciones de la sonda hasta que el monitor de perfusión registra mayor que 800 unidades de perfusión. <ol><li> Sonda firmemente en su lugar. Sondas fijado en forma incorrecta puede tener mediciones falsamente baja perfusión. </li></ol></li></ol> 3. La disección del arco aórtico / arteria subclavia <ol><li> Haga una incisión en la piel 2 cm por encima de la horquilla esternal y suavemente diseccionar la piel lejos del tejido subcutáneo. </li><li> Diseccionar la glándula submandibular libre. <ol><li> Si se presenta sangrado, presionar con suavidad puede ser aplicado con un algodón. </li><li> Divida la glándula submandibular a través de la línea media en el plano avascular. </li></ol></li><li> Levante suavemente el esternón con pinzas y con el scissSRO hacen 1 cm esternotomía media a través de la línea media del esternón. Cualquier desviación de la línea media puede resultar en hemorragia de la arteria mamaria interna que será difícil de controlar. </li><li> Coloque 5-0 suturas de retracción en cada lado en el borde del esternón y retraer esternón asegurar lateralmente suturas a la cama en funcionamiento. Evite colocar suturas de retracción demasiado lateralmente para prevenir el neumotórax. </li><li> Utilizando disección roma músculos correa libre a lo largo tráquea. El músculo correa de la izquierda se puede dividir con tijeras para mejorar la exposición. </li><li> Diseccionar liberar el timo del tejido circundante. Continuar disección roma hasta que se visualizan los grandes vasos. Tenga mucho cuidado para evitar la entrada en el espacio pleural. </li><li> Coloque las abrazaderas vasculares en el arco aórtico y la arteria subclavia izquierda. </li><li> Verifique el flujo distal ha interrumpido de manera apropiada. Esto será visto como una reducción&gt; 90% en unidades de perfusión. <ol><li> Continuar oclusión de desirojo para 4-8 min. </li></ol></li><li> Sacar la pinza vascular y verificar hemostasia antes del cierre del pecho. </li></ol> 4. Cierre de esternotomía y la piel <ol><li> Retire la sutura de retracción en el lado izquierdo del ratón. </li><li> Cierre la esternotomía con la sutura de retracción derecha. <ol><li> Una sola sutura esternal (usando la puntada de retracción colocado previamente) es adecuada para el cierre esternal. Colocar otra puntada es innecesario y aumenta los riesgos de neumotórax y hemorragia. </li></ol></li><li> Cerrar la piel con el funcionamiento de 5-0 puntada. </li></ol> 5. Evaluación y Recuperación postoperatoria <ol><li> Transferir el ratón para jaula de recuperación. Jaula debe ser colocado sobre una almohadilla de calentamiento para aumentar la temperatura ambiente de la cámara de recuperación y reducir la pérdida de calor al medio ambiente. </li><li> Vigilar de cerca el ratón en busca de signos de dificultad respiratoria o la actividad convulsiva. Administrar la analgesia por directrices de la institución. Eutharatones nize inmediatamente si se observan convulsiones o dificultad respiratoria. <ol><li> CO 2 eutanasia cámara es nuestro método preferido. La dislocación cervical es otra opción si el CO 2 no está disponible. </li><li> La recuperación completa se puede esperar en 1-2 horas, dependiendo de la longitud de anestésico volátil y la concentración usada. </li></ol></li><li> Devuelva el ratón para jaula normal. Coloque los alimentos y el lugar de agua en el suelo de la jaula. </li><li> Evaluar el estado neurológico a intervalos de 12 h utilizando Basso Ratón Escala de Locomotion 8. </li></ol>

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Los autores declaran no tener intereses financieros en competencia.

Paraplejia secundaria a la médula reperfusión isquemia de la médula es el resultado de un complejo de patologías poco comprendidos 9. Si bien esto es más frecuente después de la cirugía de la aorta toracoabdominal, una variedad de otros insultos tales como las disecciones de aorta, traumatismos, fenómenos embólicos, vasculitis, y la hipotensión sistémica 10 puede resultar en paraplejia. Para lograr una mejor comprensión de esta lesión y proporcionar objetivos futuros para eliminar esta...

Parálisis de las extremidades inferiores sigue complicando intervenciones toracoabdominal. La lesión, conocida como la médula espinal lesión por isquemia-reperfusión (SCIR), resulta en la parálisis en hasta el 20% de los pacientes de alto riesgo 1. Auxiliares quirúrgicas como el bypass cardíaco izquierdo, lumbar fluido drena cerbrospinal, paro circulatorio hipotérmico y reimplantación de la arteria intercostal han reducido la incidencia de esta complicación 2, sin embargo, demasiados pacientes continúan siendo afectados. Clínicamente, la isquemia de la médula espinal y lesión por reperfusión se considera como inmediata o tardía parálisis después de la intervención 3. Sin embargo, nuestra comprensión de esta lesión ha sido sofocado por la falta de detalles mecanicista. Como resultado, algunas opciones están disponibles para atenuar el daño una vez que ha ocurrido. Así, hemos alistado un animal pequeño, modelo murino de isquemia de la médula espinal, y la lesión de reperfusión amejor caracterizar su patogénesis. La mayoría de los estudios hasta la fecha han utilizado modelos animales más grandes para caracterizar esta lesión, a saber, la rata 4, 5 conejo, cerdo y 6 modelos. Sin embargo, éstos están limitados por su coste, la complejidad, la reproducibilidad variable y, lo más importante, la falta de técnicas disponibles para la manipulación genética. El más fiable de estos modelos animales publicados implica pinzamiento cruzado de infrarrenal de la aorta abdominal en conejos. Sin embargo, anteriores humano neuronas espinales más a menudo obtienen su suministro vascular de las ramas más proximales 7. Anatomía vascular variable de la médula espinal en estos modelos añade a la dificultad en la transición de sus resultados en el uso clínico. Este manuscrito presenta un modelo para la paraplejía inmediata o retardada después de la oclusión de la aorta torácica que es clínicamente relevante y fácil de emplear. Exposición del arco aórtico a través de mini sternotomi es menos invasivo y puede provocar resultados altamente reproducibles con mínima morbilidad y mortalidad. Si bien este modelo en no sin problemas y matices técnicos, éstos se pueden superar con una cuidadosa disección y manipulación de tejidos para producir un modelo de parálisis de las extremidades posteriores que se puede implementar fácilmente.

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			<td height="21" style="height:21px;width:216px;">VMS Anesthesia Machine</td>
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			<td height="21" style="height:21px;width:216px;">Isoflurane</td>
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			<td style="width:119px;">13985-528-60</td>
			<td>2.0% through nose cone&#160;</td>
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			<td height="21" style="height:21px;width:216px;">Laser Doppler Monitor</td>
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reproducable paraplegia by thoracic aortic occlusion in a murine model of spinal cord ischemia-reperfusion

Fondo Parálisis de las extremidades inferiores sigue complicando las intervenciones de aorta. La falta de comprensión de la patología subyacente ha obstaculizado los avances para disminuir la incidencia de esta lesión. El modelo actual demuestra menor parálisis de las extremidades reproducible después de la oclusión de la aorta torácica. Métodos Ratones C57BL6 macho adultos fueron anestesiados con isoflurano. A través de una incisión cervicosternal la aorta fue expuesto. Las arterias aorta y subclavia izquierda torácica descendente se identificaron sin entrada en el espacio pleural. Esqueletonización de estas arterias fue seguido por el cierre inmediato (Sham) u oclusión de 4 min (isquemia moderada) o 8 min (isquemia prolongada). La esternotomía y la piel se cerraron y el ratón fue trasladado a la cama calentamiento para la recuperación. Después de la recuperación, el análisis funcional se obtuvo a los 12 intervalos h hasta las 48 h. Resultados jove_content Los ratones que fueron sometidos a cirugía simulada mostraron ningún déficit de las extremidades posteriores observable. Los ratones sometidos a isquemia moderada durante 4 min tuvieron déficit funcional mínima en 12 horas, seguido de la progresión a la parálisis completa a las 48 h. Los ratones sometidos a isquemia prolongada tenían una parálisis inmediata con ningún movimiento de las extremidades posteriores observable en cualquier punto en el postoperatorio. No había observado intraoperatoria o la mortalidad postoperatoria. Conclusión Reproducible inferior parálisis de las extremidades sean inmediatos o diferidos se puede lograr en un modelo murino. Además, mediante el uso de una esternotomía mediana y disección cuidadosa, las altas tasas de supervivencia, y reproducibilidad que se puede lograr.

Los ratones se sometieron a cirugía simulada (n = 3) o de oclusión aórtica para 4 (n = 3) a 8 min (n = 3). Los ratones después de la operación se calificaron por el Score Basso ratón (Figura 1). Los ratones que fueron sometidos a cirugía simulada no tenían déficits funcionales observables en cualquier momento después de la operación. Los ratones sometidos a isquemia moderada (4 min) tenían cerca de la función normal de las extremidades posteriores, a las 12 horas con el deterioro funcional ...

Watch this Scientific Journal Video about Reproducable Paraplegia by Thoracic Aortic Occlusion in a Murine Model of Spinal Cord Ischemia-reperfusion at JoVE.com

Reproducable Paraplegia by Thoracic Aortic Occlusion in a Murine Model of Spinal Cord Ischemia-reperfusion

La falta de comprensión mecanicista de la médula espinal lesión por isquemia-reperfusión ha obstaculizado otros aditamentos para prevenir la paraplejia después de las operaciones de aorta de alto riesgo. Por lo tanto, el desarrollo de modelos animales es imperativo. Este manuscrito demuestra menor parálisis de las extremidades reproducible después de la oclusión de la aorta torácica en un modelo murino.

Paraplejia reproducible por la oclusión de la aorta torácica en un modelo murino de la médula espinal por isquemia-reperfusión

Background
Lower extremity paralysis continues to complicate aortic interventions. The lack of understanding of the underlying pathology has hindered ...

reproducable-paraplegia-thoracic-aortic-occlusion-murine-model-spinal

Research

JoVE Journal

Medicine

11.9K vistas.  University of Colorado.  La falta de comprensión mecanicista de la médula espinal lesión por isquemia-reperfusión ha obstaculizado otros aditamentos para prevenir la paraplejia después de las operaciones de aorta de alto riesgo. Por lo tanto, el desarrollo de modelos animales es imperativo. Este manuscrito demuestra menor parálisis de las extremidades reproducible después de la oclusión de la aorta torácica en un modelo murino. 

Video: Reproducable Paraplegia by Thoracic Aortic Occlusion in a Murine Model of Spinal Cord Ischemia-reperfusion

Acute and Chronic Tactile Sensory Testing after Spinal Cord Injury in Rats

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory testing in rat SCI models is needed. However, until recently, no single testing approach had been validated for SCI so that standardized methods have not been implemented across labs. Additionally, available testing methods could not be implemented acutely or when severe motor impairments existed, preventing studies of the development of SCI-induced allodynia3. Here we present two validated sensory testing methods using von Frey Hair (VFH) monofilaments which quantify changes in tactile sensory thresholds after SCI4-5. One test is the well-established Up-Down test which demonstrates high sensitivity and specificity across different SCI severities when tested chronically5. The other test is a newly-developed dorsal VFH test that can be applied acutely after SCI when allodynia develops, prior to motor recovery4-5. Each VFH monofilament applies a calibrated force when touched to the skin of the hind paw until it bends. In the up-down method, alternating VFHs of higher or lower forces are used on the plantar L5 dermatome to delineate flexor withdrawal thresholds. Successively higher forces are applied until withdrawal occurs then lower force VFHs are used until withdrawal ceases. The tactile threshold reflects the force required to elicit withdrawal in 50% of the stimuli. For the new test, each VFH is applied to the dorsal L5 dermatome of the paw while the rat is supported by the examiner. The VFH stimulation occurs in ascending order of force until at least 2 of 3 applications at a given force produces paw withdrawal. Tactile sensory threshold is the lowest force to elicit withdrawal 66% of the time. Acclimation, testing and scoring procedures are described. Aberrant trials that require a retest and typical trials are defined. Animal use was approved by Ohio State University Animal Care and Use Committee.

We describe two tactile sensory testing methods for acute or chronic periods of spinal cord injury in rats. These validated procedures can detect the development and maintenance of allodynia-like sensations.

Aguda y crónica Prueba sensorial táctil después de la lesión de la médula espinal en ratas

Spinal cord injury (SCI) impairs sensory systems causing allodynia1-8. To identify cellular and molecular causes of allodynia, sensitive and valid sensory ...

Investigación

Medicina

A Contusion Model of Severe Spinal Cord Injury in Rats

The translational potential of novel treatments should be investigated in severe spinal cord injury (SCI) contusion models. A detailed methodology is described to obtain a consistent model of severe SCI. Use of a stereotactic frame and computer controlled impactor allows for creation of reproducible injury. Hypothermia and urinary tract infection pose significant challenges in the post-operative period. Careful monitoring of animals with daily weight recording and bladder expression allows for early detection of post-operative complications. The functional results of this contusion model are equivalent to transection models. The contusion model can be utilized to evaluate the efficacy of both neuroprotective and neuroregenerative approaches.

A contusion model of severe spinal cord injury is described. Detailed pre-operative, operative and post-operative steps are described to obtain a consistent model.

Un modelo Contusión de la lesión de la médula espinal severa en ratas

The translational potential of novel treatments should be investigated in severe spinal cord injury (SCI) contusion models. A detailed methodology is ...

A Murine Model of Cervical Spinal Cord Injury to Study Post-lesional Respiratory Neuroplasticity

A cervical spinal cord injury induces permanent paralysis, and often leads to respiratory distress. To date, no efficient therapeutics have been developed to improve/ameliorate the respiratory failure following high cervical spinal cord injury (SCI). Here we propose a murine pre-clinical model of high SCI at the cervical 2 (C2) metameric level to study diverse post-lesional respiratory neuroplasticity. The technique consists of a surgical partial injury at the C2 level, which will induce a hemiparalysis of the diaphragm due to a deafferentation of the phrenic motoneurons from the respiratory centers located in the brainstem. The contralateral side of the injury remains intact and allows the animal recovery. Unlike other SCIs which affect the locomotor function (at the thoracic and lumbar level), the respiratory function does not require animal motivation and the quantification of the deficit/recovery can be easily performed (diaphragm and phrenic nerve recordings, whole body ventilation). This pre-clinical C2 SCI model is a powerful, useful, and reliable pre-clinical model to study various respiratory and non-respiratory neuroplasticity events at different levels (molecular to physiology) and to test diverse putative therapeutic strategies which might improve the respiration in SCI patients.

Respiratory failure is the leading cause of death following a cervical spinal cord injury. Having a reproducible, quantifiable, and reliable pre-clinical animal model of respiratory failure induced by a partial cervical injury will help to understand the subsequent respiratory and non-respiratory neuroplasticity and allow testing putative repair strategies.

Un modelo murino de la médula espinal cervical Lesión en estudio post-lesional Respiratorio Neuroplasticidad

A cervical spinal cord injury induces permanent paralysis, and often leads to respiratory distress. To date, no efficient therapeutics have been developed ...

A Murine Model of Myocardial Ischemia-reperfusion Injury through Ligation of the Left Anterior Descending Artery

Acute or chronic myocardial infarction (MI) are cardiovascular events resulting in high morbidity and mortality. Establishing the pathological mechanisms at work during MI and developing effective therapeutic approaches requires methodology to reproducibly simulate the clinical incidence and reflect the pathophysiological changes associated with MI. Here, we describe a surgical method to induce MI in mouse models that can be used for short-term ischemia-reperfusion (I/R) injury as well as permanent ligation. The major advantage of this method is to facilitate location of the left anterior descending artery (LAD) to allow for accurate ligation of this artery to induce ischemia in the left ventricle of the mouse heart. Accurate positioning of the ligature on the LAD increases reproducibility of infarct size and thus produces more reliable results. Greater precision in placement of the ligature will improve the standard surgical approaches to simulate MI in mice, thus reducing the number of experimental animals necessary for statistically relevant studies and improving our understanding of the mechanisms producing cardiac dysfunction following MI. This mouse model of MI is also useful for the preclinical testing of treatments targeting myocardial damage following MI.

We introduce a surgical method to induce experimental ischemia/reperfusion (I/R) injury to simulate myocardial infarction (MI) in mouse models that allows for more clarity in positioning of the ligation on the left anterior descending artery (LAD) to increase the reproducibility of MI experiments in mice.

Un modelo murino de isquemia-reperfusión miocárdica lesión a través de la ligadura de la arteria descendente anterior

Acute or chronic myocardial infarction (MI) are cardiovascular events resulting in high morbidity and mortality. Establishing the pathological mechanisms ...

A Radio-telemetric System to Monitor Cardiovascular Function in Rats with Spinal Cord Transection and Embryonic Neural Stem Cell Grafts

High thoracic or cervical spinal cord injury (SCI) can lead to cardiovascular dysfunction. To monitor cardiovascular parameters, we implanted a catheter connected to a radio transmitter into the femoral artery of rats that underwent a T4 spinal cord transection with or without grafting of embryonic brainstem-derived neural stem cells expressing green fluorescent protein. Compared to other methods such as cannula insertion or tail-cuff, telemetry is advantageous to continuously monitor blood pressure and heart rate in freely moving animals. It is also capable of long term multiple data acquisitions. In spinal cord injured rats, basal cardiovascular data under unrestrained condition and autonomic dysreflexia in response to colorectal distension were successfully recorded. In addition, cardiovascular parameters before and after SCI can be compared in the same rat if a transmitter is implanted before a spinal cord transection. One limitation of the described telemetry procedure is that implantation in the femoral artery may influence the blood supply to the ipsilateral hindlimb.

We present a protocol for using a radio-telemetric system to record cardiovascular parameters in T4 spinal cord transected rats eight weeks after embryonic brainstem neural stem cell grafting into the lesion site. Telemetry is an advanced technique to accurately evaluate cardiovascular function in conscious freely moving spinal cord injured rats.

Un sistema de radio-telemetría para monitorizar la función cardiovascular en ratas con la médula espinal y transección Embryonic Stem Neural injertos de células

High thoracic or cervical spinal cord injury (SCI) can lead to cardiovascular dysfunction. To monitor cardiovascular parameters, we implanted a catheter ...

Murine Model of Intestinal Ischemia-reperfusion Injury

Intestinal ischemia is a life-threatening condition associated with a broad range of clinical conditions including atherosclerosis, thrombosis, hypotension, necrotizing enterocolitis, bowel transplantation, trauma and chronic inflammation. Intestinal ischemia-reperfusion (IR) injury is a consequence of acute mesenteric ischemia, caused by inadequate blood flow through the mesenteric vessels, resulting in intestinal damage. Reperfusion following ischemia can further exacerbate damage of the intestine. The mechanisms of IR injury are complex and poorly understood. Therefore, experimental small animal models are critical for understanding the pathophysiology of IR injury and the development of novel therapies.
Here we describe a mouse model of acute intestinal IR injury that provides reproducible injury of the small intestine without mortality. This is achieved by inducing ischemia in the region of the distal ileum by temporally occluding the peripheral and terminal collateral branches of the superior mesenteric artery for 60 min using microvascular clips. Reperfusion for 1 hr, or 2 hr after injury results in reproducible injury of the intestine examined by histological analysis. Proper position of the microvascular clips is critical for the procedure. Therefore the video clip provides a detailed visual step-by-step description of this technique. This model of intestinal IR injury can be utilized to study the cellular and molecular mechanisms of injury and regeneration.

Here we describe the detailed procedure of intestinal ischemia-reperfusion in mice which results in reproducible injury without mortality to encourage the standardization of this technique across the field. This model of intestinal ischemia-reperfusion injury can be utilized to study the cellular and molecular mechanisms of injury and regeneration.

Modelo murino de isquemia-reperfusión intestinal Lesiones

Intestinal ischemia is a life-threatening condition associated with a broad range of clinical conditions including atherosclerosis, thrombosis, ...

Reproducible Motor Deficit Following Aortic Occlusion in a Rat Model Of Spinal Cord Ischemia

Spinal cord ischemia is a fatal complication following thoracoabdominal aortic aneurysm surgery. Researchers can investigate the strategies for preventing and treating this complication using experimental models of spinal cord ischemia. The model described here demonstrates varying degrees of paraplegia that relate to the length of occlusion following thoracic aortic occlusion in a rat spinal cord ischemia model.
A 2-Fr. balloon-tipped catheter was advanced through the femoral artery into the descending thoracic aorta until the catheter tip was placed at the left subclavian artery in anesthetized male Sprague-Dawley rats. Spinal cord ischemia was induced by inflating the catheter balloon. After a set period of occlusion (9, 10, or 11 min), the balloon was deflated. Neurologic assessment was performed using the motor deficit index at 24 h after surgery, and the spinal cord was harvested for histopathological examination.
Rats that underwent 9 min of aortic occlusion showed mild and reversible motor impairment in the hind limb. Rats subjected to 10 min of aortic occlusion presented with moderate but reversible motor impairment. Rats subjected to 11 min of aortic occlusion displayed complete and persistent paralysis. The motor neurons in the spinal cord sections were more preserved in rats subjected to shorter duration of aortic occlusion.
Researchers can achieve a reproducible hind limb motor deficit following thoracic aortic occlusion using this spinal cord ischemia model.

This study demonstrates the technique to make a minimally invasive and easily reproducible model of spinal cord ischemia in rats. Various degrees of hind limb motor deficit can be produced by controlling the aortic occlusion time.

El déficit motor reproducible después de la oclusión aórtica en un modelo de rata de la isquemia de la médula espinal

Spinal cord ischemia is a fatal complication following thoracoabdominal aortic aneurysm surgery. Researchers can investigate the strategies for preventing ...

Two-vessel Occlusion Mouse Model of Cerebral Ischemia-reperfusion

In this study, a middle cerebral artery (MCA) occlusion mouse model is employed to study cerebral ischemia-reperfusion. A reproducible and reliable mouse model is useful for investigating the pathophysiology of cerebral ischemia-reperfusion and determining potential therapeutic strategies for patients with stroke. Variations in the anatomy of the circle of Willis of C57BL/6 mice affects their infarct volume after cerebral-ischemia-induced injury. Studies have indicated that distal MCA occlusion (MCAO) can overcome this problem and result in a stable infarct size. In this study, we establish a two-vessel occlusion mouse model of cerebral ischemia-reperfusion through the interruption of the blood flow to the right MCA. We distally ligate the right MCA and right common carotid artery (CCA) and restore blood flow after a certain period of ischemia. This ischemia-reperfusion injury induces an infarct of stable size and a behavioral deficit. Peripheral immune cells infiltrate the ischemic brain within the 24 h infiltration period. Additionally, the neuronal loss in the cortical area is less for a longer reperfusion duration. Therefore, this two-vessel occlusion model is suitable for investigating the immune response and neuronal recovery during the reperfusion period after cerebral ischemia.

A mouse model of cerebral ischemia-reperfusion is established to investigate the pathophysiology of stroke. We distally ligate the right middle cerebral artery and right common carotid artery and restore blood flow after 10 or 40 min of ischemia.

Oclusión de los vasos dos ratón modelo de isquemia-reperfusión Cerebral

In this study, a middle cerebral artery (MCA) occlusion mouse model is employed to study cerebral ischemia-reperfusion. A reproducible and reliable mouse ...

Evaluation of Coronary Flow Reserve After Myocardial Ischemia Reperfusion in Rats

Coronary artery disease is the leading cause of death worldwide. After an acute myocardial infarction, early and successful myocardial intervention via recanalization of the coronary artery is the most effective strategy for reducing the size of ischemic myocardium. The coronary microvasculature cannot be visualized and imaged&#160;in vivo, but there are several invasive and noninvasive techniques that can be used to assess parameters which depend directly on coronary microvascular function. The endothelial function after ischemia reperfusion can be assessed also at the level of the coronary circulation via the coronary flow reserve (CFR).&#160;In this study, peak velocity of left anterior descending (LAD) coronary arteries was measured in rats in vivo via Transthoracic Doppler Echocardiography during resting and stress challenge (induced by Dobutamine). A normal heart can increase its coronary blood flow up to four times above the resting values during stress induction. Following ischemia reperfusion, we found a significantly diminished CFR, which can be used as a marker of coronary microvascular dysfunction. CFR has opened a window on the importance of microvascular dysfunction and has been shown to predict cardiovascular risk independent of whether the severe obstructive disease is present.

Coronary flow reserve (CFR), is defined as the ratio of maximal coronary blood flow to the resting coronary blood flow. We present a protocol for evaluating CFR in rats via ultrasound, which offers the opportunity to predict cardiovascular risk factors in the absence of obstructive coronary disease.

Evaluación de la Reserva de Flujo Coronario Después de la Reperfusión de Isquemia Miocárdica en Ratas

Coronary artery disease is the leading cause of death worldwide. After an acute myocardial infarction, early and successful myocardial intervention via ...

Murine Surgical Model of Topical Elastase Induced Descending Thoracic Aortic Aneurysm

According to the Center for Disease Control, aortic aneurysms (AAs) were considered a leading cause of death in all races and both sexes from 1999-2016. An aneurysm forms as a result of progressive weakening and eventual dilation of the aorta, which can rupture or tear once it reaches a critical diameter. Aneurysms of the descending aorta in the chest, called descending thoracic aortic aneurysms (dTAA), make up a large proportion of aneurysm cases in the United States. Uncontained dTAA rupture is almost universally lethal, and elective repair has a high rate of morbidity and mortality. The purpose of our model is to study dTAA specifically, to elucidate the pathophysiology of dTAA and to search for molecular targets to halt the growth or reduce the size of dTAA. By having a murine model to study thoracic pathology precisely, targeted therapies can be developed to specifically test dTAA. The method is based on the placement of porcine pancreatic elastase (PPE) directly on the outer murine aortic wall after surgical exposure. This creates a destructive and inflammatory reaction, which weakens the aortic wall and allows for aneurysm formation over weeks to months. Though murine models possess limitations, our dTAA model produces robust aneurysms of predictable size. Furthermore, this model can be used to test genetic and pharmaceutical targets which may arrest dTAA growth or prevent rupture. In human patients, interventions such as these could help avoid aneurysm rupture, and difficult surgical intervention.

We describe a surgical protocol to consistently induce robust descending thoracic aortic aneurysms in mice. The procedure involves left thoracotomy, thoracic aorta exposure, and placement of a sponge soaked in porcine pancreatic elastase on the aortic wall.

Modelo Quirúrgico Murino de Aneurisma aórtico torácico descendente fortuito tópico

According to the Center for Disease Control, aortic aneurysms (AAs) were considered a leading cause of death in all races and both sexes from 1999-2016. ...